Analysis of Factors Influencing Natural Killer (NK) Cell Activity during the Early Phase after Allogeneic Stem Cell Transplantation (SCT).

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2192-2192
Author(s):  
Lars Fischer ◽  
Olaf Penack ◽  
Chiara Gentilini ◽  
Eckhard Thiel ◽  
Uharek Lutz
Keyword(s):  
T Cell ◽  
Nk Cells ◽  
Nk Cell ◽  
Absolute Number ◽  
Cell Depletion ◽  
Reduced Intensity Conditioning ◽  
T Cell Depletion ◽  
The Mean ◽  
The Absolute

Abstract Background: After allogeneic SCT, NK cell mediated cytotoxicity is an important defense mechanism against residual tumor cells and viral infections. Using a novel flow cytometric assay, which detects the lytic granule membrane protein CD107a as a marker for NK cell degranulation, we investigated the effect of in vivo T cell depletion and the type of conditioning on NK cell function in the early phase after transplantation. Methods: At day +30 and day +90 after allogeneic SCT with regular (n=14) and dose reduced conditioning (n=8), PBMCs were coincubated at 37°C for 3 h with the NK sensitive cell line HL60. 20μl of PE-Cy5 conjugated anti-CD107a monoclonal antibody (moAb) was added to each tube containing 400μl effector/target cell suspension (2x106 cells, E:T ratio 1:1) prior to incubation. After 1 hour, 10μl of monensin (2mM) was added. After incubation for 3 hours, the cells were stained with conjugated moAb (CD56, CD16, CD3) for flow cytometry. The percentage of CD107a expressing NK cells was assessed and the absolute number of degranulating NK cells /μl was calculated. Results were compared to values from 15 healthy controls. Results: Twenty two patients (pts.) were investigated. Fourteen pts. received a conventional conditioning regimen and eight a reduced intensity conditioning. T cell depletion was applied in 15/22 pts. (ATG n=12, alemtuzumab n=2, 1 OKT-3 n=1). The type of donor included MRD (n=7) and MUD (n=15). At day +30, the proportion of NK cells with cytotoxic activity (indicated by the mean percentage of degranulating CD107a+/CD56+ cells) was significantly reduced as compared to normal donors (2.6% vs. 5.6%, p<0.001). At day +90 the percentage of degranulating NK cells was still decreased compared to normal (3.5%, p=0.007). The predominant proportion of degranulating cells was in the CD56dim/CD16− subpopulation (mean 9.8%). After conventional conditioning, the mean percentage of CD107a+ cells was 1,9% at day +30, compared to 4,0% in patients with reduced intensity conditioning (p=0.21). The absolute number of degranulating NK cells was significantly reduced after conventional conditioning (4.1/μl vs. 19.8/μl, p=0.011). Interestingly, we found no influence of in vivo T cell depletion with ATG on the mean value for CD107a+ cells at day +30 (2.5% vs. 2.9%, p=0.77). Conclusion: Although the proportion of NK cells is increased after allogeneic SCT, our data suggest that the cytotoxic activity of these cells is considerably reduced. The absolute number of NK cells with cytotoxic activity is significantly higher after reduced intensity conditioning which may contribute to the effectiveness of these regimens. Antibody induced in vivo T cell depletion with ATG showed no impact on NK cell activity during the first two months post SCT.

Alemtuzumab but Not ATG Decreases Natural Killer (NK) Cell Activity towards Tumor Targets in the Early Phase after Allogeneic Stem Cell Transplantation.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2869-2869
Author(s):  
Olaf Penack ◽  
Lars Fischer ◽  
Andrea Stroux ◽  
Chiara Gentilini ◽  
Axel Nogai ◽  
...  
Keyword(s):  
T Cell ◽  
Nk Cells ◽  
Early Phase ◽  
Nk Cell ◽  
Cell Activity ◽  
Absolute Number ◽  
Cell Depletion ◽  
Nk Cell Activity ◽  
T Cell Depletion ◽  
Healthy Donors

Abstract Background: In vivo T cell depletion with ATG or Alemtuzumab is effective to reduce the incidence of graft-versus host disease (GVHD) caused by alloreactive T cells. However, there is also a potential impact of these substances on the function of natural killer (NK) cells who are the predominant cells in peripheral blood in the early phase after hematopoietic stem cell transplantation (HSCT) and mediate beneficial graft-versus-tumor activity. Using a novel flow cytometric assay, which detects the lytic granule membrane protein CD107a as a marker for NK cell degranulation, we investigated the effect of T cell depletion with ATG and Alemtuzumab on NK cell function in the early phase after HSCT. Methods: PBMCs of 34 patients (pts) at day +30 after allogeneic HSCT and of 16 healthy donors were coincubated at 37°C for 3 h with the NK sensitive cell line HL60. In each tube, containing 400μl effector/target suspension (2x106 cells), 20μl of PE-Cy5 conjugated anti-CD107a monoclonal antibody was added prior to incubation. After the first 1 h 10μl of the secretion inhibitor 2 mM monensin was added. At the end of coincubation cells were stained with mAbs (CD56, CD3) for flow cytometry. The percentage of CD107a expressing NK cells was assessed and the absolute number of degranulating NK cells/μl was calculated. Results: Treatment Characteristics: Fourteen pts received ATG, ten pts were treated with Alemtuzumab and ten patients did not receive T cell depletion. The source of donor was: MRD 12 and MUD 22. NK cell count: The median NK cell count was: 250/μl in healthy individuals, 250/μl in pts without T cell depletion, 400/μl in pts with ATG and 100/μl in pts receiving Alemtuzumab (p<0.0005; Kruskal-Wallis test). NK cell activity: The median percentage of degranulating NK cells was 5.4% in healthy donors, 4,4% without T cell depletion, 2,8% when ATG was used and 0,8% when Alemtuzumab was given (p<0.0005). The absolute number of CD107a+ NK cells in response to the standardized tumor targets accounted for 13,4/μl (median) in normal donors, 12,9/μl in pts without T cell depletion, 7,6/μl in pts with ATG and 0,9/μl in pts with Alemtuzumab (p=0.001). The percentage and absolute number of CD107a+ NK cells were not significantly different between patients receiving ATG and patients not receiving T cell depletion (p=NS). Conclusion: With a new and feasible method we were able to quantify and characterize tumor reactive NK cells after HSCT. We found that NK cell mediated cytotoxicity towards tumor targets is influenced by the type of T cell depletion: The NK cell activity in patients receiving Alemtuzumab was considerably reduced whereas ATG had only moderate impact on the NK cell activity in the early phase after HSCT.

scholarly journals Increased Inhibitory KIR-Ligand Interactions Confer Relapse Protection Following HLA Matched Unrelated Donor HCT for AML

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 47-47
Author(s):  
Elizabeth Krieger ◽  
Rehan Qayyum ◽  
Amir Ahmed Toor
Keyword(s):  
T Cell ◽  
Nk Cell ◽  
Interaction Analysis ◽  
Donor Selection ◽  
Cell Depletion ◽  
Unrelated Donor ◽  
Cell Transplant ◽  
T Cell Depletion ◽  
Relapse Risk

Killer immunoglobulin-like receptor (KIR) and KIR-ligand (KIRL) interactions play an important role in natural killer cell-mediated graft versus leukemia effect (GVL) after hematopoietic stem cell transplant (HCT) for AML. There is considerable heterogeneity in the KIR gene and KIRL content of individuals, making it difficult to estimate the full clinical impact of NK cell alloreactivity following HCT. Herein, we validate a mathematical model accounting for KIR-KIRL interactions identifying donors with optimal NK cell-mediated alloreactivity and GVL. This retrospective study was performed on de-identified donor and recipient demographic and clinical outcomes data provided by the Center for International Blood and Marrow Transplant Research (CIBMTR). Donor recipient pairs (DRP) who underwent unrelated donor (URD) HCT for early and intermediate AML were included. KIR-KIRL interaction values were assigned as follows; if an inhibitory KIR (iKIR) on the NK cell encounters a ligand on its target, this will give the NK cell an inhibitory signal and this is scored as a single interaction(Figure 1b), as is the case, if there is no ligand for an inhibitory KIR, i.e., missing KIRL (mKIRL) (Figure 1c). Finally, activating KIR (aKIR) interacting with its ligands is similarly scored(Figure 1a). The absolute values of the iKIR and mKIR scores were summed to calculate the composite inhibitory-missing ligand (IM)-KIR score (Figure 1d). The study cohort was comprised of 2365 donor-recipient pairs (DRP) who underwent URD HCT for early or intermediate AML. Mean age was 53 years; 85% of DRPs were high-resolution 8/8 HLA-matched for HLA-A, -B, -C, and -DRB1. All patients received T cell replete grafts; 42% (n=996) received in vivo T cell depletion, 937 (94%) with anti-thymocyte globulin (ATG); 86% received a graft of mobilized peripheral blood stem cells (PBSC), 59% received myeloablative conditioning. This cohort was primarily of Caucasian descent (89%). When adjusted for recipient age, donor age, CMV status, KPS, GVHD prophylaxis, cytogenetics, disease status, conditioning regimen, in vivo T cell depletion, graft source, and sex match, relapse risk was significantly reduced in donor-recipient pairs (DRP) with higher inhibitory KIR-KIRL interaction and missing KIRL (mKIR) scores, with HR=0.86 (P=0.01) & HR=0.84 (P=0.02) respectively. This effect was not observed with activating KIR-KIRL interactions. Chronic GVHD and TRM were not significantly affected by iKIR, mKIR or aKIR. Given the significant individual impact of iKIR and mKIR, the summed inhibitory-missing ligand (IM-KIR) score was next assessed, and when this score was 5 (as opposed to &lt;5), the IM-KIR score was also associated with lower relapse risk, HR 0.8 (P=0.004) (Figure 2a). Acute and chronic graft vs. host disease (GVHD), survival, GRFS, and relapse-free survival were not significantly different, likely due to increased TRM among these patients, HR 1.32 (P=0.01). Interaction analysis indicated that amongst the HLA matched DRP, ATG recipients with IM-KIR=5, had a lower relapse rate compared to those with an IM-KIR&lt;5, HR 0.61 (p=0.001) (Figure 2b), among the cohort who did not receive ATG there was no significant difference in relapse among IM-KIR=5 and IM-KIR&lt;5; thus, the use of ATG significantly modified the effect of IM KIR score in an interaction analysis (p=0.049), suggesting higher NK cell magnitude of KIR-KIRL interaction may compensate for the general increase of relapse in those who receive in vivo T cell depletion. Nevertheless, TRM was also increased in these patients, HR 1.49 (p=0.034), likely abrogating survival advantage from a lower relapse risk. This large international study confirms that unrelated DRPs with greater magnitude of inhibitory KIR-KIRL interactions confer significant relapse protection after MUD HCT in standard-risk AML. This challenges the notion that KIR are irrelevant to donor selection. Future clinical trials evaluating donor selection for URD HCT should include this measure to evaluate its value prospectively in uniformly treated patient cohorts, with adequate GVHD and antiviral prophylaxis to mitigate TRM. Disclosures No relevant conflicts of interest to declare.

Allo-Reactive NK Cells after HLA-Matched Allogeneic Hematopoietic Stem Cell Transplantation.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2904-2904
Author(s):  
Justin Hasenkamp ◽  
Andrea Borgerding ◽  
Bjoern Chapuy ◽  
Gerald Wulf ◽  
Inga Missal ◽  
...  
Keyword(s):  
Stem Cell ◽  
T Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Nk Cells ◽  
Nk Cell ◽  
Cell Depletion ◽  
T Cell Depletion ◽  
Hematopoietic Stem ◽  
Graft Versus Host ◽  
Donor Type

Abstract Allo-reactive natural killer (NK) cells frequently occur early after haplo-mismatch hematopoietic stem cell transplantation (HSCT) with killer cell immunoglobuline-like receptor (KIR)-ligand mismatch in graft versus host (GvH) direction. Clinical data and experiments in mice indicate a beneficial influence on relapse rates, graft acceptance and Graft-versus-Host disease (GvHD). We determined the incidence of allo-reactive donor type NK cells after HLA A-, B-, DR-, DQ-matched allogeneic HSCT on a functional level. Clinical course, chimerism (PCR), immune-reconstitution (FACS) and frequencies of functional active and allo-reactive NK cells (ELISpot) were longitudinal determined in 19 patients so far. Patients (pts) suffered for high risk AML (7 pts), CML failing cytogenetic response to imatinib (3 pts), poor risk ALL (2 pts), relapse/refractory high-grade NHL (6 pts) and Multiple Myeloma (13q-) (1 pt). All patients received myeloablative conditioning regimens and GvHD-prophylaxis with cyclosporine A or tacrolimus and short course mycophenolat mofetil without in vivo or ex vivo T cell depletion. Chimerism analyses ensured hematopoietic reconstitution from donor type in 19/19 patients. In 3/19 patients NK cell activity was absent even against HLA class I negative control target cells. Absence of functional active NK cells correlates with severe acute GvHD accompanied by high doses of glucocorticosteroid medication. In all other patients we detected at least once functional active NK cells in peripheral blood. In 4/19 cases we detected allo-reactive NK cells after HSCT at days (d) +28, +68, +128 (case 19), d +56 (case 8), d +355 (case 1) and d +379 (case 13). Two cases were transplanted in KIR-ligand mismatch in GvH direction (donors HLA-CAsn80 and -CLys80, recipients missing HLA-CLys80). Allo-reactive NK cells were absent in all patients with known complete KIR-ligand match. Flow cytometry data on reconstitution of NK cell repertoire showed individual heterogeneous results. After median observation time post HSCT of 268 d (31–902) 3 patients died due to relapse. None of the patients with NK cell allo-reactivity experienced relapse. This is the first proof of circulating functionally active, allo-reactive NK cells after HLA-A, -B, -DR and -DQ matched HSCT. We detected NK cell allo-reactivity in all donor-recipient pairs with KIR-ligand (HLA-C) mismatch in GvH direction. After haplo-mismatch HSCT and T cell depletion NK cell allo-reactivity is restricted early after transplantation (within 3 months). In contrast, we detected late onset (>1 year) of NK cell allo-reactivity after one-locus (HLA-C) mismatch HSCT without T cell depletion of the grafts.

Comparison of Unrelated and Sibling Donor Allogeneic Hematopoietic Cell Transplantation (HCT) for Follicular Lymphoma (FL) - From the Lymphoma Working Party, European Group for Blood and Marrow Transplantation (EBMT) and Center for International Blood and Marrow Transplant Research (CIBMTR).

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 874-874
Author(s):  
Marcelo C. Pasquini ◽  
Mei-Jie Zhang ◽  
Parameswaran N Hari ◽  
Silvia Montoto ◽  
Ginna G. Laport ◽  
...  
Keyword(s):  
T Cell ◽  
Treatment Failure ◽  
Cell Depletion ◽  
Unrelated Donor ◽  
Reduced Intensity Conditioning ◽  
T Cell Depletion ◽  
Allogeneic Hct ◽  
Autologous Hct ◽  
Reduced Intensity

Abstract Abstract 874 Allogeneic HCT is potentially curative in FL, but wide adoption of this treatment is limited by its toxicity and donor availability. Improvements in HLA-matching have improved the safety of unrelated donor (URD) HCT. We compared the outcomes of 702 recipients of allogeneic HCT for FL (198 URD and 504 sibling donors (sib)) from 171 centers world-wide reporting to the CIBMTR or EBMT between 1997 and 2005. Recipients of mismatched, cord blood or ex vivo T-cell depleted grafts were excluded. Overall and progression-free survival (OS and PFS), transplant-related mortality (TRM) and relapse/progression outcomes were analyzed using Cox proportional hazards regression models with donor type (sib vs. URD) as the main effect. URD HCT was performed more frequently after 2001. Comparing to the sib group, URD HCT recipients were more likely to receive reduced intensity conditioning (70% vs. 54%), antithymocyte globulin or alemtuzumab (in vivo T-cell depletion) or tacrolimus-based graft-versus host disease (GVHD) prophylaxis, and have a longer interval from diagnosis to HCT (median 49 vs. 32 months). URD HCT recipients had poorer risk FL with more pre-transplant chemotherapy, including previous autologous HCT (36% vs. 16%) and prior exposure to rituximab (66% vs. 43%) compared with sib HCT recipients. Adjusted probabilities for three-year PFS and OS were 49% vs. 60% (p=0.02) and 54% vs. 69% ( p<0.001) for URD and sib HCT, respectively. Cumulative incidence of acute GVHD (grade 2-4) at day 100 was 48% and 42% (p=0.3), whereas chronic GVHD at one year was 47% and 41% (p=0.3) for the URD and sib HCT respectively. Relative risks for TRM, relapse/progression, treatment failure and mortality, comparing URD to sib donors, are shown below. Significant risk factors associated with worse outcomes included poor performance status at transplantation and extensive pre-transplant therapy (> 4 lines of therapy or prior autologous HCT). Additionally, in vivo T-cell depletion was associated with a higher risk of relapse/progression and treatment failure. Reduced intensity conditioning was associated with lower TRM, but did not impact other outcomes. In conclusion, this study shows that URD HCTs are performed later in the treatment course for FL, in higher risk patients, most commonly with reduced intensity conditioning, and are associated with worse PFS and OS compared to sib HCT. Considerations for future studies include the use of URD allogeneic HCT earlier in the course of treatment for FL and avoiding T cell depleting agents in the conditioning regimen.Outcome#URD/SibURD vs. sib RR1 (95% CI)P TRM197/5002.04 (1.43 - 2.90)<0.0001 Relapse/Progression197/5000.97 (0.61 - 1.52)0.8781 Treatment Failure2197/5001.49 (1.11 - 2.01)0.0087 All cause Mortality3198/5041.91 (1.40 - 2.61)<0.00011Relative Risk2Relapse/Progression or Death3Opposite of OS Disclosures: No relevant conflicts of interest to declare.

Hematopoietic Chimerism Following Non-Myeoloablative Stem Cell Transplantation Is Dependent on NK Cell Tolerance.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 45-45
Author(s):  
Geert Westerhuis ◽  
Wendy G. Maas ◽  
Roelof Willemze ◽  
Rene E. Toes ◽  
Willem E. Fibbe
Keyword(s):  
T Cells ◽  
T Cell ◽  
Nk Cells ◽  
Nk Cell ◽  
Cell Depletion ◽  
Cell Tolerance ◽  
Spleen Cells ◽  
Elimination Kinetics ◽  
Donor Cells

Abstract NK cells are able to eliminate major mismatched hematopoietic cells and, in addition to T cells, represent a second barrier that prevents engraftment following transplantation over MHC barriers. Here, we studied the role of NK cells in the elimination of major mismatched hematopoietic cells in a Balb/c into B6 transplantation model after anti-CD40L (MR1) treatment. In this model, survival of donor cells was determined using an in-vivo cytotoxicity assay based on the infusion of differentially CFSE-labeled syngeneic and donor splenocytes. Likewise, the efficacy of treatment was determined directly by assessing the level of chimerism three months after transplantation. Four weeks after the infusion of 106 bone marrow cells (BMC), B6 mice rejected donor spleen cells within 3 hours. A combination with anti-CD40L treatment prevented this early elimination and these mice showed the same elimination kinetics as observed in untreated mice (97.0 ± 1.3% vs. 96.6 ± 1.3% in 3 days). These results indicate that anti-CD40L treatment prevents the induction of a memory T cell response after infusion of donor BMC. Nonetheless, elimination of donor cells was still present within 3 days, therefore we hypothesized that the elimination of donor cells was mediated by NK cells, rather than by T cells. A detailed analysis of the elimination kinetics in untreated B6 mice showed that the CFSE-labeled Balb/c splenocytes were gradually eliminated starting from the moment of infusion. Similar elimination kinetics were observed in T cell-deficient B6 nu/nu mice. In addition, in-vivo treatment with a depleting anti-NK cell antibody (PK136) prolonged the survival of donor splenocytes in both B6 and B6 nu/nu mice (54.7 ± 2.8% vs. 8.4 ± 5.9% in 2 days in B6 mice and 72.4 ± 7.2% vs. 19.4 ± 8.6% in 1 day in B6 nu/nu mice). A similarly prolonged survival of donor spleen cells was observed in NK cell-depleted mice that had received 106 BMC 4 weeks earlier in combination with anti-CD40L (77.4 ± 15.6% with NK cell depletion vs. 5.3 ± 0.6% without NK cell depletion in 2 days), while no effect was observed after in-vivo treatment with a depleting anti-CD8 antibody. Infusion of increasing numbers of Balb/c BMC (106, 107, 108) after treatment with anti-CD40L resulted in a dose-dependent prolongation of the survival of donor splenocytes, but up to 108 BMC were needed for complete non-responsiveness. This indicated that transplantation of 108 BMC resulted in tolerization of NK cells, which was also associated with stable chimerism (36.1 ± 14.0% of the GR-1+ fraction). In-vivo depletion of NK cells before transplantation allowed stable chimerism in mice treated with anti-CD40L and only 30 x 106 BMC (5/5 vs. 1/5 without NK cell depletion). These data demonstrate that: 1) The elimination of Balb/c donor splenocytes in untreated B6 recipient mice is mediated by NK cells. 2) In mice treated with donor BMC and anti-CD40L the elimination of donor splenocytes can be delayed by NK cell depletion or by increasing the initial dose of donor BMC. 3) NK cell tolerance over MHC barriers can be induced by transplantation of a high number of BMC (108) and results in sustained engraftment and chimerism. 4) Additional NK cell depletion allows sustained chimerism following transplantation of a lower number (30 x 106) of BMC. We conclude that the induction of NK cell tolerance is dependent on the dose of donor BMC injected. This may explain the high numbers of BMC required for engraftment over MHC barriers.

Mature T Cells in the Graft Improve NK Cells Reconstitution after Haploidentical Hematopoietic Stem Cell Transplantation.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3120-3120
Author(s):  
Stephanie Nguyen ◽  
Mathieu Kuentz ◽  
Jean-Paul Vernant ◽  
Nathalie Dhedin ◽  
Oualid Bouteraa ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Nk Cells ◽  
Nk Cell ◽  
Cell Depletion ◽  
Specific Lysis ◽  
T Cell Depletion ◽  
Donor T Cells ◽  
Nk Cell Differentiation

Abstract We previously demonstrated that natural killer (NK) cells generated after haploidentical stem-cell transplantation (SCT) are blocked at an immature state characterized by phenotypic features and impaired functioning, a blockage that may affect transplantation outcome (Nguyen et al. Blood 2005). Hypothesizing that the absence of mature donor T cells in the graft may affect NK cell differentiation and function, we examined NK cells from 21 patients who received haploidentical SCT from relatives for advanced malignant hematopoietic disease and underwent either partial (pTCD) (CD3+ in the graft >1x105/Kg, mean: 6.9x105/Kg; n=11) or extensive (e-TCD) (CD3+ in the graft<1x105/Kg; mean: 0.35x105/Kg; n=10) T cell depletion and compared them with NK cells from their healthy donors. As previously described, compared with donor cells, recipient NK cells expressed lower levels of inhibitory KIR (in particular KIR2DL1 and KIR2DL2) and higher levels of CD94/NKG2A receptors after transplant (mean expression of CD94/NKG2A on recipient NK cell at 3 months post-transplant: 93.4%±7.2% versus 49.6%±10.9% on donor NK cells, p<0.0001), but these levels did not differ significantly between the pTCD and eTCD groups. However, the frequency of the immunoregulatory CD3−CD56bright NK subset was sharply lower in the pTCD than eTCD groups after transplantation (25.0%±9.6% versus 53.3%±18.0 at 3 months; p<0.001). The level of NKp30 receptors on NK cells was also higher after pTCD than eTCD transplantation (70.3%±7.1% versus 58.0%±6.5%, p=0.013) and that of pTCD patients resembled the donor NK repertoire. NK cytotoxicity against primary haplomismatched AML blasts was significantly more pronounced after pTCD than eTCD transplants (29.0%±8.9% specific lysis versus 6.7%±4.1% at a ratio Effector/Target (E/T):20/1, p=0.002), although still lower than in donor NK cells (mean specific lysis of donor NK cells from both groups against AML blasts: 43.5%±13% at a ratio E/T: 20/1). This more mature phenotypic and functional profile of NK cells after pTCD transplant was clinically associated with a lower rate of relapse and superior survival (1/11 relapse, 3/11 patients alive in complete remission at 11, 10 and 3 years) than in eTCD group (8/10 relapse; no patient alive at 1 year). These results support a model in which mature donor T cells in the graft may play a key role, in vivo, in NK cell differentiation by improving NK cell maturation and cytolytic function against leukemic blasts. They point to the dilemma of haploidentical hematopoietic SCT in leukemic patients: on the one hand, extensive T-cell depletion is associated with a risk of fatal leukemia relapse due to the loss of the GvL effect T cells, which can not be replaced by immature NK cells; on the other hand, partial T-cell depletion might increase the risk of GvHD but also improves the GvL effect mediated by NK cells. New treatments infusing mature haploidentical NK cells in leukemic patients should be used to test the efficiency of NK alloreactivity.

scholarly journals Impact of CD3+ and CD34+ Doses in the Mobilized Peripheral Blood Stem Cell Grafts on the Outcome of Reduced-Intensity Conditioning Allogenic Transplantation from Matched Unrelated Donors for Acute Myeloid Leukemia – an Analysis from the Acute Leukemia Working Party of the EBMT

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 190-190
Author(s):  
Tomasz Czerw ◽  
Myriam Labopin ◽  
Christoph Schmid ◽  
Jan J. Cornelissen ◽  
Patrice Chevallier ◽  
...  
Keyword(s):  
T Cell ◽  
Myeloid Leukemia ◽  
Cell Depletion ◽  
Reduced Intensity Conditioning ◽  
T Cell Depletion ◽  
Cd34 Cells ◽  
Unrelated Donors ◽  
Grade 3 ◽  
The Impact

Abstract Introduction: The impact of peripheral blood stem cell (PBSC) grafts composition on the outcome of reduced-intensity conditioning (RIC) allogenic transplantations (allo-SCT) is still controversial. Inconsistent results have been reported regarding the influence of CD3+ and CD34+ cells dose on incidence of GVHD, disease control and survival. These discrepancies may be at least in part explained by the differences in disease categories, disease status at transplant, donor type and conditioning. Aim and methods: This retrospective EBMT registry study aimed to analyze the impact of CD3+ and CD34+ cells dose in PBSC grafts on the outcome of RIC allo-SCT in patients with acute myeloid leukemia (AML) allografted from matched unrelated donors (MUD). Two hundred and three adults with AML in first complete remission (CR1) treated with RIC allo-PBSCT from MUD (10 of 10 match) between 2000 and 2012 (median 2011) were included. Ex-vivo T-cell depletion was an exclusion criterion. Median age was 58 (range, 21-73) years; gender: male-116, female-87; 142 had intermediate, 42 unfavorable, 4 favorable, and 15 unknown cytogenetic features; median time to achieve CR1 was 51 (range, 21-350) days, whereas time from CR1 to allo-SCT was 115 days (15-351). Median donor age was 34 (range, 19-61) years. The preparative regimen was based on chemotherapy in 143 (70%) of the RIC allo-CST (Flu-Bu:110; Flu-Mel:12; Flu-Treosulfan:14, other:7), whereas in 60 (30%) low dose TBI was applied (2 Gy:57; 4 Gy:3). In-vivo T-cell depletion (ATG or Campath) was used in 166 (82%) of the transplants. Median transplanted CD3+ and CD34+ doses were 250 (50-885) x 10^6 and 6.53 (1.34-413) per kg of recipient b.w., respectively. Follow-up was 22 months (3-105). Results: The engraftment rate equaled 99% (202 pts) and was not affected by CD3+ nor CD34+ counts. In univariate analysis, patients transplanted with the highest CD3+ doses (above the third quartile cut-off point value, >347 x 10^6/kg) had an increased incidence of acute (a) GVHD grade >2 (45% vs. 26%, p=0.007) and grade 3-4 (20% vs. 6%, p=0.003), respectively. In the quartile of pts transplanted with the highest CD34+ graft content (>8.25 x 10^6 /kg) increased incidence of grade 3-4 aGVHD (18% vs. 7%, p=0.02) was observed. Other risk factors for aGVHD were transplantation from CMV seropositive donors (grade >2; 44% vs. 24%, p=0.005) and from females to males (grade 3-4; 19% vs. 8%, p=0.04). There was no association between cellular composition of grafts and non-relapse mortality (NRM), AML relapse, incidence of chronic (c) GVHD and survival. There was also no significant correlation between CD3+ and CD34+ cells infused. In multivariate analysis, CD3+ dose was the only adverse predicting factor for aGVHD grade >2 (HR= 2.1; 95%CI: 1.25-3.55, p=0.005) and together with CD34+ dose for aGVHD grade 3-4 (CD3+, HR=3.6; 95%CI: 1.45-9.96, p=0.006; CD34+, HR=2.65; 95%CI: 1.07-6.57, p=0.04). Other factors that independently affected unfavorable outcome were: time from diagnosis to CR1 above median for NRM, transplantation without in-vivo T-cell depletion for cGVHD, time from CR1 to allo-SCT above median and unfavorable karyotype for leukemia-free and overall survival and unfavorable karyotype for relapse incidence. Conclusions: These results suggest that the incidence of severe acute GVHD post RIC allo-SCT, still a major cause of morbidity and mortality, is associated with the composition of the PBSC grafts, specifically higher numbers of infused CD3+ and CD34+ cells. As graft composition can be manipulated, careful assessing the CD3+ and CD34+ graft content and the cell dose infused may help in reducing severe aGVHD risk and improving transplantation outcome. Disclosures No relevant conflicts of interest to declare.

Prophylactic Natural Killer Cell Immunotherapy Following HLA-Haploidentical Hematopoietic Cell Transplantation Prevents Relapse and Improves Survival in Patients with High-Risk Hematological Malignancies

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1161-1161 ◽  
Author(s):  
Monica Thakar ◽  
Parameswaran Hari ◽  
David G. Maloney ◽  
Carolyn A. Keever-Taylor ◽  
Lori Jones ◽  
...  
Keyword(s):  
Overall Survival ◽  
T Cell ◽  
High Risk ◽  
Nk Cells ◽  
Hematopoietic Cell Transplantation ◽  
Nk Cell ◽  
Progression Free Survival ◽  
Cell Depletion ◽  
T Cell Depletion ◽  
Free Survival

Abstract Background: Regimens using post-transplant cyclophosphamide (CY) have been developed to provide potent in vivo T cell depletion for patients undergoing human leukocyte antigen (HLA)-haploidentical hematopoietic cell transplantation (HCT). Luznik, O'Donnell and colleagues (BBMT 2008) reported that when this immune suppression strategy is coupled with non-myeloablative conditioning (fludarabine 150 mg/m2, CY 29 mg/kg, 2 Gy total body irradiation) followed by marrow transplantation, it was well-tolerated with low rates of non-relapse mortality (NRM; 15% at 1 year). However, the 2 year overall survival (OS) and event-free survival were low at 36% and 26%, respectively, due to high relapse rates (51% at 1 year). One explanation could be that while post-HCT CY promoted low rates of acute graft-versus-host disease (GVHD), it also eliminated early T and natural killer (NK) cell clones important for disease surveillance. Based on this hypothesis, we developed a next-generation Phase I/II clinical trial incorporating a boost of donor NK cells on day +7 as an attempt to prevent relapse after transplant. In this study, CY 50 mg/kg as a single dose on day +3 was used for T cell depletion. Methods: Forty patients (pediatric, n=14; adult, n=26) with median age of 45 (range 8-75) years having ALL (n=11), AML (n=9), MDS (n=6), HL (n=6), MM (n=4), NHL (n=3), and CLL (n=1) underwent non-myeloablative transplantation using related, HLA-haploidentical marrow donors on this prospective clinical trial. Patients were high risk due to underlying disease, potential for relapse, and/or risk for transplant-related mortality (TRM). Most patients were heavily pre-treated, with median time from cancer diagnosis to transplant being 2 (0.3 - 12.1) years, including 18 patients having 26 prior HCTs (auto, n=14; allo, n=12). Twenty-five patients (63%) had HCT-CI scores ≥ 3 indicating high risk for TRM. In order to obtain NK cells, non-mobilized peripheral blood mononuclear cells were collected from donors on day +6 using apheresis and stored overnight. NK cells were isolated on day +7 using the Miltenyi CliniMACS system (CD3 depletion followed by CD56 selection) and were administered as a single, fresh infusion that same day without prior culturing or expansion. The Phase I dose-finding study (n=11) enrolled at 2 NK doses [2.5 or 5 x 106/kg +/- 20%, respectively], with extended enrollment at the 2nd dose level for Phase II (n=29) with 83% of patients meeting NK dose parameters. NK cell products had a median log T cell depletion of 5.4 (4.1-7.1), median NK recovery of 54% (33-68%), and median NK purity of 92% (74-99%). Excellent viability (>95%) was seen in all NK products. Results: One patient developed chest pain associated with NK cell infusion; otherwise all other patients tolerated their NK cell infusions well without fevers or other adverse reactions. Full donor chimerism (>95% CD3) was seen in 83% of patients at last follow-up, while 18% and 10% experienced graft rejection or graft failure, respectively. Cumulative incidence of grades 2-3 and grade 3 (no grade 4 seen) acute GVHD occurred in 36% and 8% of patients, respectively, at day +100. Of the 39 evaluable patients, 16% developed chronic extensive GVHD at 1 year. Relapse or progression occurred in 31% of patients by 1 year after HCT. With a median follow-up of 1.5 years (range, 0.1 - 4.9 years), 14 patients have died from relapse/progression (n=11) or infection/VOD (n=3), giving a probability of OS, relapse/progression-free survival (PFS), and NRM at 1 year of 73%, 62%, and 8%, respectively, and 2 year OS and relapse/PFS of 63% and 46%, respectively (Fig 1). Summary: We have demonstrated the safety of infusing donor NK cells early after HCT in a group of heavily-treated patients with high-risk hematological malignancies. In many patients, disease-free survival was possible with the aid of this prophylactic infusion of donor NK cells in combination with allogeneic HCT. These results provide a promising platform to further augment NK cell alloreactivity in the post-HCT setting to prevent relapse and disease progression. Figure 1 Incidence of Overall Survival and Relapse/Progression-Free Survival Figure 1. Incidence of Overall Survival and Relapse/Progression-Free Survival Disclosures Hari: Merck: Research Funding; BMS: Honoraria.

Sign in / Sign up

Export Citation Format

Share Document